Premium
Purification and properties of phenylalanyl aminopeptidase synthesised by Pseudomonas sp.
Author(s) -
Jankiewicz Urszula,
Bielawski Wieslaw
Publication year - 2002
Publication title -
journal of basic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.58
H-Index - 54
eISSN - 1521-4028
pISSN - 0233-111X
DOI - 10.1002/1521-4028(200208)42:4<260::aid-jobm260>3.0.co;2-9
Subject(s) - aminopeptidase , chemistry , chromatography , enzyme , substrate (aquarium) , ion chromatography , enzyme assay , size exclusion chromatography , iodoacetamide , affinity chromatography , hydrolysis , cysteine , biochemistry , nuclear chemistry , amino acid , biology , leucine , ecology
Intracellular aminopeptidase synthesized by a soil strain of Pseudomonas sp. was purified 323‐fold using the following procedure: saturation with ammonium sulfate, separation by preparative electrophoresis, anion‐exchange chromatography and gel filtration chromatography. Molecular weight of the enzyme determined according to the latter method was 57 kDa. Aminopeptidase showed a high substrate specificity and affinity to Phe‐ β ‐naphtylamide (Phe‐ β ‐NA) as a substrate. A considerable inhibition of the enzymatic activity by iodoacetamide and p ‐chloromercuribenzoate ( p ‐CMB) led to the conclusion that it was a cysteine aminopeptidase. Hydrosulphide compounds markedly stabilised the enzyme. Ethylenediaminetetra‐acetic acid (EDTA), a metalloenzyme inhibitor, caused a double increase in the phenylalanyl aminopeptidase activity. Mg 2+ ions activated the enzyme to a negligible extent, whereas Co 2+ , Cu 2+ , Cd 2+ and Pb 2+ ions contributed to its inhibition. The highest enzymatic activity was observed at 37 °C and pH 7.0.